不同生境甜槠黄酮类化合物含量及成分分析

运用分光光度法测定了来自浙江台州境内天台山不同生境的甜槠黄酮类化合物的含量并对其成分进行了聚酰胺薄层层析分析。结果表明,甜槠不同生境的叶片黄酮类化合物以冠层生境含量最高,灌丛生境次之,林下生境含量最低;林下生境的黄酮类化合物成分最少,而冠层生境的成分最多。     

Random and blocked practice of movement sequences: differential effects on response structure and movement speed

Three similar six-element key press sequences were practiced under blocked or random practice schedules with acquisition conducted on one day and retention and transfer on the next day. The task required participants to type, as quickly as possible, one of three 6-element sequences as observed on a computer monitor. In blocked practice, participants completed all practice in one repeated sequence before the next repeated sequence was introduced. In random acquisition practice, the three repeated sequences were randomly presented to the participants. The data suggest that random practice results in participants adopting a uniform response structure, while blocked practice allows participants to exploit unique sequential aspects of the individual tasks. This finding suggests that random practice may not be as effective as blocked practice when one of the tasks being practiced together can be optimized through the development of a unique response structure.     

Do High-Quality Kindergarten and First-Grade Classrooms Mitigate Preschool Fadeout?

Prior research shows that short-term effects from preschool may disappear, but little research has considered which environmental conditions might sustain academic advantages from preschool into elementary school. Using secondary data from two preschool experiments, we investigate whether features of elementary schools, particularly advanced content and high-quality instruction in kindergarten and first grade, as well as professional supports to coordinate curricular instruction, reduce fadeout. Across both studies, our measures of instruction did not moderate fadeout. However, results indicated that targeted teacher professional supports substantially mitigated fadeout between kindergarten and first grade but that this was not mediated through classroom quality. Future research should investigate the specific mechanisms through which aligned preschool-elementary school curricular approaches can sustain the benefits of preschool programs for low-income children.     

Web 2.0 and Information Literacy Instruction: Aligning Technology with ACRL Standards

The purpose of this article is to report on how Web 2.0 tools in an online information literacy instruction course aligned with ACRL's Information Literacy Competency Standards for Higher Education. A qualitative case study was undertaken on an online graduate course related to information literacy instruction. Data collected included: course activities, assignments, emails, online discussions, and surveys. The educational theory of constructivism and its adherence to reflection, active learning, and social interaction was used to find patterns in the data. Activity theory provided a framework for data analysis and interpretation related to the patterns of activities that took place while students used each Web 2.0 tool. Web 2.0 was found to enhance all five information literacy standards. These standards related to collaboration, information organization, creativity, discussion, and technology education.     

Does early childhood education help to improve high school outcomes? Results from Tulsa

Early childhood education contributes to improved school readiness but impacts on high school remain unclear. This study estimates the effects of Tulsa, Oklahoma's universal pre-K and Head Start programs through the junior year of high school (in 2018/2019; N = 2902; M_age = 16.52, SD = .39; 48% female; 28% white, 34% Black, 27% Hispanic, 8% Native American). Propensity score weighted regressions suggest students who attended pre-K, but not Head Start, missed less school, were less likely to fail courses and be retained in grade, were more likely to take an Advanced Placement/International Baccalaureate course, but did not have higher test scores or grades. Subgroup analyses by race/ethnicity demonstrated some differences in the pattern of associations favoring students of color.     

大规模定制下供应链柔性灰关联度量分析

在大规模定制生产的基础上,对大规模定制供应链柔性的进行研究.在提出和界定柔性系数这一概念和影响它的六个主要因子的基础上,利用灰关联方法科学的计算出影响大规模供应链柔性关键因子,并以某家电企业实际数据为例进行实证分析.     

The 2000 Cohort of New Assistant Professors of Counselor Education: Reflecting at the Culmination of Six Years

This article features the final phase of a 6‐year inquiry focused on counselor educators who assumed their first full‐time faculty position in the fall 2000 academic term. Through in‐depth interviews and questionnaires, the participants described their experiences addressing (a) work environment, (b) sources of satisfaction and pleasure, (c) the interplay between professional and personal domains, and (d) change and transformation. References to tenure and promotion became frequent and prominent across all themes. Recommendations for counselor‐educators‐in‐training, candidates, new counselor educators, and veteran counselor educators are provided.